The Cooling and Humidifying Effects and the Thresholds of Plant Community Structure Parameters in Urban Aggregated Green Infrastructure

Abstract

The cooling and humidifying effects of urban aggregated green infrastructure can provide essential services for city ecosystems, regulating microclimates or mitigating the urban heat island effect. However, the optimal thresholds of plant community structure parameters for maximizing the associated cooling and humidifying effects remain unclear. In this paper, we use the method of dummy variable regression to measure plant communities in an urban aggregated green infrastructure. By examining the relationships between the cooling and humidifying effects and plant community structure parameters (i.e., canopy density, porosity, and vegetation type), we introduce optimal thresholds for the parameters. We find that canopy density has a significantly positive correlation with both cooling and humidifying effects, while porosity has a positive correlation with cooling and a negative one with humidifying. Different vegetation types have distinct influences on cooling and humidifying effects. When the canopy density is between 0.81 and 0.85 and the porosity is between 0.31 and 0.35, the cooling and humidifying effects of the plant communities reach their peak. Additionally, the greening coverage rate and spatial types of urban aggregated green infrastructure have influences on cooling and humidifying effects. The findings can help us to better understand the relationships between plant community structure parameters and their temperature regulation functioning for urban aggregated green infrastructure. This study provides guidelines and theoretical references for the plant configuration of future urban green spaces.

Bioindication of megalopolis park ecosystems under aerotechnogenic loading

“…Climate change within the metropolis compared to its surroundings, terrain, loss of green areas in recent decades, the spread of areas covered with asphalt and concrete, significant construction and loss of heating networks increase the temperature of ground layers, reduce relative humidity and change the wind regime. High density of highways causes intense gassiness and air pollution (Shevchenko and Snizhko 2008;Van Wittenberghe et al 2012;Wei et al 2021). Stagnant phenomena contribute to the intensive accumulation of impurities in the city.…”

“…Greenery is important for urban systems because it absorbs air and dust pollutants (Pietras-Couffignal and Robakowski 2019; Jaung et al 2020;Jin et al 2021); additionally, it cools and humidifies the air, regulates the microclimate and mitigates the urban heat island effect (Vieira et al 2018;Jaung et al 2020;Wei et al 2021). In summer, greenery helps to reduce the air temperature by 4°С−6°С and increase the humidity by 10%−15%.…”

“…Bioindication studies in the anthropogenic load gradient of Kyiv were performed (Rabosh and Kofanova 2019;Miroshnyk 2018;Mazura et al 2020). Because greenery is important for maintaining air quality and microclimate in cities (Jaung et al 2020;Jin et al 2021;Wei et al 2021), it is important and necessary to comprehensively study the viability of park ecosystems (PEs) under anthropogenic pressure. That is why we chose Kyiv city -as a landmark -because it is the largest city in the country with a population of 3 million people.…”

Lowering the Temperature to Increase Heat Equity: A Multi-Scale Evaluation of Nature-Based Solutions in Toronto, Ontario, Canada

“…Green infrastructure has been shown to have a positive effect on near-surface air temperatures and LST, as a result of shading and evapotranspiration [38,39]. The temperature regulation benefits of green infrastructure vary by application and are influenced by factors including irrigation, local climate, physical dimension, seasonality, and vegetation.…”

“…Temperature regulation through the application of green walls occurs through shade provision, reduced reflected heat, and evapotranspiration [50,64,65]. During the summer season, green walls can Green infrastructure has been shown to have a positive effect on near-surface air temperatures and LST, as a result of shading and evapotranspiration [38,39]. The temperature regulation benefits of green infrastructure vary by application and are influenced by factors including irrigation, local climate, physical dimension, seasonality, and vegetation.…”